[seam-dev] automatic loading of persistence units in JBoss AS 5

One of the changes in JBoss AS 5 that comes as a surprise for many Seam developers/users familiar with the behavior of JBoss AS 4 is the automatic loading of persistence units from /META-INF/persistence.xml. (As expected, we had to change several of the Seam examples to accommodate this change). This is one of those configuration by exception features in Java EE 5, with one significant exception. While the container will locate the /META-INF/persistence.xml file on its own, a container that goes by the book will only deploy the persistence unit if a resource reference is declared in the descriptor file (web.xml or ejb-jar.xml). JBoss AS does not wait for this signal. In my opinion, there is a problem with the JBoss AS approach. What if you have persistence units that you don't want to deploy? One use case is that you have persistence units for different environments and a configuration file can toggle between them. Another use case is that you have another library, such as Spring or Seam, which bootstraps the persistence unit instead. Sure, you could rename the file, but then you break all the IDE behavior that expects the file to be named persistence.xml. Personally, I think there should be some way to disable the behavior in JBoss AS and make it look for the persistence unit references. I agree to keep the automatic loading as the default, but it is pretty inconvenient not to be able to disable it. Anyone else agree? Disagree? Why? -Dan -- Dan Allen Software consultant | Author of Seam in Action http://mojavelinux.com http://mojavelinux.com/seaminaction NOTE: While I make a strong effort to keep up with my email on a daily basis, personal or other work matters can sometimes keep me away from my email. If you contact me, but don't hear back for more than a week, it is very likely that I am excessively backlogged or the message was caught in the spam filters. Please don't hesitate to resend a message if you feel that it did not reach my attention.